It is well known to input text or data or to control a cursor of a computer, laptop, personal digital assistant, video game, vending machine, Automated Teller Machine at a bank, security panel, etc., via a keyboard, touch pad, key pad, mouse, track ball, joystick, touch sensitive screen, and the like. There have been improvements such that the user does not need to physically touch the input device to control the computer. For example, U.S. Pat. No. 6,313,825 (Gilbert) teaches an input device for a computer that detects movement of an object such as a finger within a field of space to input commands into the computer. The input device uses infrared radiation or ultrasonic waves to illuminate and sense the detection field for the user's finger or hand movements. U.S. Pat. No. 5,821,922 (Sellers) uses a video camera mounted on a laptop to detect hand movements in a region above the keyboard, wherein the hand movements are translated into cursor movements. U.S. Pat. No. 6,421,042 (Omura et al.) uses light projected over a writing surface which when interrupted by a finger is detected by CCD cameras. Data from the cameras are then converted via deciphering software into command codes for operating a computer, AV equipment, a DVD player, etc.
U.S. Pat. No. 6,130,663 (Null) discloses a touchless input apparatus, wherein the apparatus uses rotating drums with helical slits that cyclically emit infrared radiation to a field above the apparatus. Finger movement in that field is detected, and timing and triangulation software are used to convert finger movement to control signals for the computer. U.S. Pat. No. 6,791,531 (Johnston et al.) discloses a computer input controller, wherein infrared radiation is directed to a field above a keyboard, and a user's finger gestures is detected through an imaging lens by a CCD sensor. The sensor and associated electronics convert the data to computer control commands. U.S. Pat. No. 6,281,878 (Montellese) discloses a similar input device using a light sensor positioned to sense reflections from an illuminated field, which field acts as a virtual template for a keyboard, keypad, button panel.